[学习笔记] 在Eclipse中使用Hibernate,并创建第一个Demo工程,数据库为Oracle XE

前文参考:Oracle 11g xe 在windows安装

在Eclipse中使用Hibernate

安装 Hibernate Tools 插件

https://tools.jboss.org/downloads/

Add the following URL to your Eclipse 4.13 (2019-09) installation, via:

Help > Install New Software… > Work with:

http://download.jboss.org/jbosstools/photon/stable/updates/

Then select the individual features that you want to install:

点击Next

点击Next
同意相关协议,点击Finish .

则会开始下载安装。

视网络速度,可能需要几分钟到十几分钟的时间才能完成安装。

最后会提示重启Eclipse才能生效。

在Eclipse中新建Hibernate应用

File->New -> Java Project

点击Finish

项目结构图
项目结构图

在Eclipse中新建用户库

此时下面显示了已经建立的用户库列表

我们要添加Hibernate的依赖库,因此点击用户库

Hibernate_4.3.5_final

选择jar文件

项目结构图

继续配置Hibernate

最后自动形成 如下的文件内容:[本例使用oracle数据库]

Oracle 11g xe 在windows安装请看如下链接:

Oracle 11g xe 在windows安装

hibernate.cfg.xml

 <?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE hibernate-configuration PUBLIC
        "-//Hibernate/Hibernate Configuration DTD 3.0//EN"
        "http://www.hibernate.org/dtd/hibernate-configuration-3.0.dtd">
<hibernate-configuration>
    <session-factory>
        <property name="hibernate.connection.driver_class">oracle.jdbc.driver.OracleDriver</property>
        <property name="hibernate.connection.password">123456</property>
        <property name="hibernate.connection.url">jdbc:oracle:thin:@localhost:1521:xe</property>
        <property name="hibernate.connection.username">test</property>
        <property name="hibernate.default_schema">test</property>
        <property name="hibernate.dialect">org.hibernate.dialect.Oracle10gDialect</property>
    </session-factory>
</hibernate-configuration>

再增加几个属性

配置文件更新后的内容如下: 注意要去掉name属性 更改

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE hibernate-configuration PUBLIC "-//Hibernate/Hibernate Configuration DTD 3.0//EN"
                                         "http://www.hibernate.org/dtd/hibernate-configuration-3.0.dtd">
<hibernate-configuration>
 <session-factory >
  <property name="hibernate.connection.driver_class">oracle.jdbc.driver.OracleDriver</property>
  <property name="hibernate.connection.password">123456</property>
  <property name="hibernate.connection.url">jdbc:oracle:thin:@localhost:xe:orcl</property>
  <property name="hibernate.connection.username">test</property>
  <property name="hibernate.default_schema">test</property>
  <property name="hibernate.dialect">org.hibernate.dialect.Oracle10gDialect</property>
  <property name="hibernate.show_sql">true</property>
  <!-- 第一次加载hibernate时根据model类会自动建立起表的结构(前提是先建立好数据库),以后加载hibernate时根据 model类自动更新表结构,即使表结构改变了但表中的行仍然存在不会删除以前的行。要注意的是当部署到服务器后,表结构是不会被马上建立起来的,是要等 应用第一次运行起来后才会。 -->
  <property name="hibernate.hbm2ddl.auto">update</property> 
  <property name="hibernate.format_sql">true</property>
  <property name="hibernate.default_entity_mode">pojo</property>
 </session-factory>
</hibernate-configuration>

继续完善工程Hibernate_demo_001

新建一个包:mytest001.demo

在包mytest001.demo之下新建一个PO类: Emp

package mytest001.demo;

public class Emp {
    // 员工的标识属性
    private Integer id;
    // 姓名
    private String name;
    // 年龄
    private Integer age;
    // 工资 (分)
    private Integer salary;

    public Integer getId() {
        return id;
    }

    public void setId(Integer id) {
        this.id = id;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public Integer getAge() {
        return age;
    }

    public void setAge(Integer age) {
        this.age = age;
    }

    public Integer getSalary() {
        return salary;
    }

    public void setSalary(Integer salary) {
        this.salary = salary;
    }

    @Override
    public String toString() {
        return "Emp [id=" + id + ", name=" + name + ", age=" + age + ", salary=" + salary + "]";
    }
}

此刻此PO Emp.java 尚不具备持久化能力。下面为其添加注解。

@Entity 注解声明该类是一个Hibernate持久化类
@Table 指定该类映射的表,对应的数据库表名是T_EMP
@Id 指定该类的标识属性,映射到数据库的主键列
@GeneratedValue(strategy=GenerationType.SEQUENCE) 指定了主键生成策略,由于本文使用Oracle Database, 因此指定了使用 SEQUENCE

在hibernate.cfg.xml中增加持久化映射类名

增加一个新类:EmpManager,用于管理员工。

package mytest001.demo;

import org.hibernate.Session;
import org.hibernate.SessionFactory;
import org.hibernate.Transaction;
import org.hibernate.cfg.Configuration;
import org.hibernate.service.Service;
import org.hibernate.service.ServiceRegistry;
import org.hibernate.service.ServiceRegistryBuilder;


public class EmpManager {

    public static void main(String[] args)  throws Exception  {
         
    //实例化配置
    Configuration configuration  = new Configuration()
            //不带参数则默认加载hibernate.cfg.xml
            .configure();
    
    ServiceRegistry serviceRegistry = new ServiceRegistryBuilder()
            .applySettings(configuration.getProperties()).build();
    SessionFactory sFactory = configuration.buildSessionFactory(serviceRegistry);
    
    //创建session 
    Session session = sFactory.openSession();
    
    //开始事务
    Transaction tx = session.beginTransaction();
    //创建员工对象
    Emp emp = new Emp();
    // 设置员工信息
    emp.setAge(28);
    emp.setName("scott");
    emp.setSalary(10000);
    session.save(emp);
    // 提交事务
    tx.commit();
    session.close();
    sFactory.close();
            
    
    }

}

最后配置文件的内容:hibernate.cfg.xml

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE hibernate-configuration PUBLIC "-//Hibernate/Hibernate Configuration DTD 3.0//EN"
                                         "http://www.hibernate.org/dtd/hibernate-configuration-3.0.dtd">
<hibernate-configuration>
 <session-factory >
  <property name="hibernate.connection.driver_class">oracle.jdbc.driver.OracleDriver</property>
  <property name="hibernate.connection.password">123456</property>
  <property name="hibernate.connection.url">jdbc:oracle:thin:@localhost:1521:xe</property>
  <property name="hibernate.connection.username">test</property>
  <property name="hibernate.default_schema">test</property>
  <property name="hibernate.dialect">org.hibernate.dialect.Oracle10gDialect</property>
  <property name="hibernate.show_sql">true</property>
  <!-- 第一次加载hibernate时根据model类会自动建立起表的结构(前提是先建立好数据库),以后加载hibernate时根据 model类自动更新表结构,即使表结构改变了但表中的行仍然存在不会删除以前的行。要注意的是当部署到服务器后,表结构是不会被马上建立起来的,是要等 应用第一次运行起来后才会。 -->
  <property name="hibernate.hbm2ddl.auto">update</property> 
  <property name="hibernate.format_sql">true</property>
  <property name="hibernate.default_entity_mode">pojo</property>
  <mapping class="mytest001.demo.Emp"/>
 </session-factory>
</hibernate-configuration>

Emp.java

package mytest001.demo;

import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.persistence.Id;
import javax.persistence.Table;

@Entity
@Table(name="T_EMP")
public class Emp {
    // 员工的标识属性
    @Id
    @GeneratedValue(strategy=GenerationType.SEQUENCE)
    private Integer id;
    // 姓名
    private String name;
    // 年龄
    private Integer age;
    // 工资 (分)
    private Integer salary;

    public Integer getId() {
        return id;
    }

    public void setId(Integer id) {
        this.id = id;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public Integer getAge() {
        return age;
    }

    public void setAge(Integer age) {
        this.age = age;
    }

    public Integer getSalary() {
        return salary;
    }

    public void setSalary(Integer salary) {
        this.salary = salary;
    }

    @Override
    public String toString() {
        return "Emp [id=" + id + ", name=" + name + ", age=" + age + ", salary=" + salary + "]";
    }
}

最后的工程结构如下:

运行EmpManger

十一月 23, 2019 8:50:47 上午 org.hibernate.annotations.common.reflection.java.JavaReflectionManager <clinit>
INFO: HCANN000001: Hibernate Commons Annotations {4.0.4.Final}
十一月 23, 2019 8:50:47 上午 org.hibernate.Version logVersion
INFO: HHH000412: Hibernate Core {4.3.5.Final}
十一月 23, 2019 8:50:47 上午 org.hibernate.cfg.Environment <clinit>
INFO: HHH000206: hibernate.properties not found
十一月 23, 2019 8:50:47 上午 org.hibernate.cfg.Environment buildBytecodeProvider
INFO: HHH000021: Bytecode provider name : javassist
十一月 23, 2019 8:50:47 上午 org.hibernate.cfg.Configuration configure
INFO: HHH000043: Configuring from resource: /hibernate.cfg.xml
十一月 23, 2019 8:50:47 上午 org.hibernate.cfg.Configuration getConfigurationInputStream
INFO: HHH000040: Configuration resource: /hibernate.cfg.xml
十一月 23, 2019 8:50:47 上午 org.hibernate.cfg.Configuration doConfigure
INFO: HHH000041: Configured SessionFactory: null
十一月 23, 2019 8:50:47 上午 org.hibernate.engine.jdbc.connections.internal.DriverManagerConnectionProviderImpl configure
WARN: HHH000402: Using Hibernate built-in connection pool (not for production use!)
十一月 23, 2019 8:50:47 上午 org.hibernate.engine.jdbc.connections.internal.DriverManagerConnectionProviderImpl buildCreator
INFO: HHH000401: using driver [oracle.jdbc.driver.OracleDriver] at URL [jdbc:oracle:thin:@localhost:1521:xe]
十一月 23, 2019 8:50:47 上午 org.hibernate.engine.jdbc.connections.internal.DriverManagerConnectionProviderImpl buildCreator
INFO: HHH000046: Connection properties: {user=test, password=****}
十一月 23, 2019 8:50:47 上午 org.hibernate.engine.jdbc.connections.internal.DriverManagerConnectionProviderImpl buildCreator
INFO: HHH000006: Autocommit mode: false
十一月 23, 2019 8:50:47 上午 org.hibernate.engine.jdbc.connections.internal.DriverManagerConnectionProviderImpl configure
INFO: HHH000115: Hibernate connection pool size: 20 (min=1)
十一月 23, 2019 8:50:48 上午 org.hibernate.dialect.Dialect <init>
INFO: HHH000400: Using dialect: org.hibernate.dialect.Oracle10gDialect
十一月 23, 2019 8:50:48 上午 org.hibernate.engine.transaction.internal.TransactionFactoryInitiator initiateService
INFO: HHH000399: Using default transaction strategy (direct JDBC transactions)
十一月 23, 2019 8:50:48 上午 org.hibernate.hql.internal.ast.ASTQueryTranslatorFactory <init>
INFO: HHH000397: Using ASTQueryTranslatorFactory
十一月 23, 2019 8:50:48 上午 org.hibernate.tool.hbm2ddl.SchemaUpdate execute
INFO: HHH000228: Running hbm2ddl schema update
十一月 23, 2019 8:50:48 上午 org.hibernate.tool.hbm2ddl.SchemaUpdate execute
INFO: HHH000102: Fetching database metadata
十一月 23, 2019 8:50:48 上午 org.hibernate.tool.hbm2ddl.SchemaUpdate execute
INFO: HHH000396: Updating schema
十一月 23, 2019 8:50:48 上午 org.hibernate.tool.hbm2ddl.DatabaseMetadata getTableMetadata
INFO: HHH000262: Table not found: T_EMP
十一月 23, 2019 8:50:48 上午 org.hibernate.tool.hbm2ddl.DatabaseMetadata getTableMetadata
INFO: HHH000262: Table not found: T_EMP
十一月 23, 2019 8:50:48 上午 org.hibernate.tool.hbm2ddl.DatabaseMetadata getTableMetadata
INFO: HHH000262: Table not found: T_EMP
十一月 23, 2019 8:50:48 上午 org.hibernate.tool.hbm2ddl.SchemaUpdate execute
INFO: HHH000232: Schema update complete
Hibernate: 
    select
        test.hibernate_sequence.nextval 
    from
        dual
Hibernate: 
    insert 
    into
        test.T_EMP
        (age, name, salary, id) 
    values
        (?, ?, ?, ?)
十一月 23, 2019 8:50:48 上午 org.hibernate.engine.jdbc.connections.internal.DriverManagerConnectionProviderImpl stop
INFO: HHH000030: Cleaning up connection pool [jdbc:oracle:thin:@localhost:1521:xe]

到数据库中查询表:(这个表会被自动创建)
select * from t_emp;

如果再次运行会增加新的记录。

至此,本文完成。

posted @ 2019-11-23 08:54  我有目标  阅读(...)  评论(...编辑  收藏